Not Applicable.
Not Applicable.
The present invention relates to a novel valve assembly for a gas dispensing nozzle to allow a user to better regulate the flow of fuel through the fuel dispensing nozzle, and more particularly to a valve assembly which allows a user to controllably dispense small amounts of fuel through such a nozzle.
Fuel dispensing nozzles are long known in the art, and are used throughout the world to enable a user to controllably regulate the flow of fuel from a storage tank into a user tank, such as a gasoline tank in an automobile. In order to facilitate the rapid and efficient dispensing of the fuel from a storage tank to a user tank, fuel dispensing systems are designed to operate at a very high fluid flow rate. The fuel is pumped from the storage tank and through a metering system that tracks and records the amount of fuel dispensed by each user. The fuel then flows through a fuel line from the metering system to a dispensing nozzle that is placed in an orifice attached to the user tank to enable the dispensing of fuel from the storage tank into the user tank.
Generally, the typical dispensing nozzle includes a handle that actuates a spring-loaded valve within the nozzle. When the handle is squeezed by the user, the valve opens to allow fuel to flow freely through the valve, through the nozzle, and into the user tank. When the handle is released, the spring shuts the valve, and thereby shuts off the flow of fuel. A variety of poppet valve configurations, also known in the art, are often used for this purpose in existing fuel dispensing nozzles.
Due to the desirability of high fuel flow rates, and the need for a reliable, positive shut-off of fuel for safety purposes, the spring that operates the poppet valve in most dispensing nozzles is very strong and requires a substantial force to compress.
Typically, the handles on dispensing nozzles operate as cantilevers to enable the user to overcome the force of the valve spring. Unfortunately, this flow control scheme is somewhat course, and the arrangement therefore offers the user only limited control over the amount of fuel dispensed through the dispensing nozzle. Historically, while such limited control over the dispensing of fuel was often a nuisance to the user, demand for more precise control did not warrant modification of the fuel dispensing systems. Recently, however, economic conditions and the rising costs of fuel have driven demand for more precise control over the dispensing of fuels, particularly in developing countries.
Accordingly, it would be desirable to have a valve assembly design that not only allows a user to dispense fuel at a rapid flow rate, but also allows the user to control the amount of fuel dispensed with more precision than current valve designs afford. Further, it would be desirable for such a valve assembly to be compatible with, and could be readily incorporated into, existing dispensing nozzles, without the need to reconfigure or modify the existing nozzle design.
The present invention resides in a valve assembly design that incorporates both an outer poppet for regulating the rapid flow of fuel, and an inner poppet for regulating a slower flow of fuel that can be controlled more precisely by the user. This double poppet valve can be incorporated into existing fuel dispensing nozzles that presently employ more traditional poppet valves without requiring modification to the nozzle.
When the handle for a nozzle housing such a double poppet valve is squeezed with sufficient force to overcome the primary spring atop the valve, the outer poppet opens to allow fuel to flow rapidly through the nozzle. Releasing the handle allows the valve spring to close the valve and shut off the flow of fuel.
Yet, the inner poppet itself is spring-loaded within the double poppet valve. However, the magnitude of the spring force on the inner poppet is less than magnitude of the force applied to the outer poppet by the valve spring.
Accordingly, when the nozzle handle is squeezed gently, with sufficient force to overcome the spring force on the inner poppet but insufficient to overcome the spring force on the outer poppet, an opening forms about the inner poppet.
The opening is smaller than the opening that forms about the outer poppet when open, and therefore will only allow fuel to flow through the nozzle at a rate less than the rate about the outer poppet when open. This allows the user to more precisely control the amount of fuel dispensed through the nozzle by more rapidly and easily shutting off the flow of fuel when a desired amount of fuel has been dispensed.
Hence, the present invention provides a simple to operate mechanism that enables a user to more precisely regulate the amount of fuel the user wishes to dispense through a fuel dispensing nozzle in the form of a double poppet valve within the nozzle that readily replaces more traditional poppet valves in existing fuel dispensing nozzles without the need to modify such nozzles.
The present invention is readily adaptable to numerous shapes and sizes, and may be constructed of many materials, such as fibers, plastics and metals.